This is a continuation of U.S. application Ser. No. 10/659,438 filed Sep. 11, 2003, (now U.S. Pat. No. 6,820,788), which is a continuation of U.S. application Ser. No. 10/119,721 filed Apr. 11, 2002 (now U.S. Pat. No. 6,641,018), which is a continuation of U.S. application Ser. No. 09/861,546 filed May 22, 2001 (now U.S. Pat. No. 6,394,332). The entire disclosures of the prior applications, application Ser. Nos. 10/659,438, 10/119,721, and 09/861,546 are considered part of the disclosure of the accompanying continuation application and are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a nail gun that drives a nail through, for example, the hole of a connection clasp and to a nail gun that can accurately drive nails into a desired drive position.
2. Description of the Related Art
A variety of different types of clasp fixing nail guns have been proposed. U.S. Pat. No. 5,193,730 discloses a nail gun that separates nails one at a time from a nail band and supplies the nail to a nail injection hole of the nosepiece. The nail tip is protruded from the end of the nosepiece before the nail gun drives the nail.
The nail gun further has a safety mechanism with a work-piece contact member, an intermediate lever, and an operation lever. The work-piece contact member extends from the nose of the nail gun to the base of the intermediate lever. When the trigger of the nail gun is pressed, the operation lever moves toward or away from an activation plunger, depending on the position of the work-piece contact member and the intermediate lever. That is, the work-piece contact member is raised into its lowermost position as long as the nose of the nail gun is not pressed against a work piece. If the trigger is pressed at this time, the intermediate lever pivots greatly and guides movement of the operation lever away from the activation plunger. On the other hand, when the nose of the nail gun is pressed against a work piece, the contact member is raised into its upper position. If the trigger is pulled at this time, pivoting movement of the intermediate lever is restricted so that the operation lever moves into contact with the activation plunger, thereby setting off a nail driving operation. In other words, the safety mechanism prevents the nail gun from firing when no work piece is present by changing the pivot path of the operation lever.